The invention relates to circuit breakers in general and more particularly to a locking arrangement for electric circuit breakers with a latch and a locking strap which cooperates with the latter and is rotatably or tiltably supported by means of two pivots lying on a common ideal axis in support openings in stationary parts, wherein the cross section of the pivots is rectangular and one of the small surfaces of the pivots can respectively be acted upon by the force to be locked.
A locking arrangement of this type is disclosed, for instance, in U.S. Pat. Nos. 3,178,535 and 3,796,980. In these arrangements, the support opening has the shape of a tetragon with two surfaces arranged at an angle to each other. The approximately knife edge-like support of the locking strap can be made by simple cutting operations that can be carried out by machine, and is therefore suitable for switching equipment that is to be produced in large quantities. However, the load carrying capacity of the locking strap is relatively low because relatively high stresses, which lead to rapid wear, occur at the edges of the small surface of the pivots acted upon by the locking force. In addition, the force cycle is dependent on the number of switching cycles.